Field of the Invention
The invention relates to a process for treating radioactive waste which occurs in the form of contaminated, powdery ion exchange resin.
Such processes are used for reducing the volume of the quantity of waste. European Patent No. 0 126 060 B1 discloses processes used for that purpose in which a mixture of ion exchange resins is heated in the presence of water and a substance giving an alkaline reaction, until the onset of decomposition of the anion exchange resins and the release of amines. In that case, temperatures of up to 280.degree. C. are required.
As tests have shown, the ion exchange resins in that case retain a significant part of their water absorption capability in spite of the not inconsiderable expenditure of energy for the heating. With regard to swelling processes associated with the water absorption, the proportion of ion exchange resins incorporated in a matrix, for example of cement or bitumen, must not exceed 10% of the mass of the waste product. That has the consequence of providing only an unsatisfactory reduction in the volume of the quantity of waste.
Derwent Abstract AN 86-158976 of Published Japanese Application 61 091 600 also already discloses a process for treating radioactive waste in the form of contaminated, powdery ion exchange resin, according to which the resin is dewatered, then mixed with a calcium compound and finally dried. That process also ensures only an unsatisfactory reduction in volume of the quantity of waste. The result is also not changed by adding drying to that process at temperatures of up to 120.degree. C. according to Published International Application WO 85/00922.